WALTHAM ‘ The Celtics are one of the most talkative teams in the NBA, and no one knows that better than Doc Rivers. On Saturday Rivers invoked a ‘no talking’ rule on offense during practice.

‘I just told everybody today that they were too loud and so I said we’re going to have a non-talk practice for the next half hour,’ he explained.

The rule, however, turned out to be difficult to enforce. The players joked that Rivers was running a communist practice and had a hard time following along with the temporary restriction.

‘That’s a little thing that Doc feels as though that once we get to talking smack to each other here in practice that we lose our focus. But the intensity’s there, but we lose our focus,’ said Rasheed Wallace. ‘On some plays he’s right but I think that’s just the character of some of the guys here in the gym. But hey, if that’s what Doc wants, we’ve got to try to do that. We’ve got to try to talk a little more quietly, that’s all.’

Even though Rivers knew the rule would be broken, he felt it was important to make the point.

‘Have you ever seen our guys quiet? That’s what was so amazing. They were saying they couldn’t talk yet everybody was talking,’ River said with a laugh, later adding, ‘There’s no such thing [silence] with this team. This is a very verbal team, which is a good thing actually, but sometimes we want to make sure we keep it under control.’

WALTHAM — Ray Allen left Celtics practice on Saturday after getting unintentionally elbowed above the left eye and knocked to the ground by Kendrick Perkins, who was playing on the same team. Allen received stitches and is not expected to miss any games.

“The sad thing is it was a skeleton offense. There was no defense,” said Doc Rivers. “We run a lot of hand-off stuff as you know and it didn’t go well. It was a hand-off with Perk and Perk had his elbow up while he was supposed to be handing it off to Ray. And those are the ones that hurt because you don’t expect those cuts to come at that time.”

Allen hit the ground grabbing his eye, according to Rivers who initially thought Allen was joking. “All of a sudden he was laying down and all of a sudden you saw the blood and said, ‘Oh no, I don’t think he’s faking.'”

“We’re still going hard, still intense,” he said. “Unfortunately it happened but we can’t sit up here and be sad and be down on ourselves, like oh man Ray got hurt. No, we’ve still got to go out there and play.”

The Celtics open their season on Tuesday night in Cleveland against the Cavaliers.

UPDATE: Allen received five stitches at New England Baptist Hospital, according to Celtics team officials.

This year, the Celtics are likely to do away with many shootarounds on the day of a game and move practices to a slightly later start in the day so that players can sleep in and be well-rested for games.

“Later practices are alright,” Kevin Garnett said on Friday. “It is what it is. Whatever Doc wants. It’s not my cup of tea but whatever the Captain wants that’s what it is.”

Garnett is a notorious early riser and has a reputation of functioning on little or no sleep, especially following road trips. Garnett, like Junior Seau with the Patriots, is known for getting to work early in the morning, getting warmed up and ready to go with practice.

Now, he’s likely going to be able to sleep in, at least a little.

“I don’t sleep anyway,” Garnett said. “It’s good. You’ve got to find good in everything so if that means I get to sleep until 8:30 or 9 [a.m.], then so be it.”

On Saturday Glen Davis will roll up his sleeves to roll burritos for a group of Celtics fans at Chipotle Mexican Grill in Cambridge from 3:30-4:30pm. Five WEEI contest winners as well as ten local youth from BELL (Building Educated Leaders for Life) will enjoy lunch courtesy of Big Baby. Davis will also film a promotional video for Chipotle which will air during Celtics home games. All those in attendance will play extras in the video. On Friday the Celtics announced Chipotle Mexican Grill has become an official team partner.

WALTHAM — Kevin Garnett reached his breaking point on Friday afternoon with questions about whether he is physically ready and back to 100 percent following surgery last May to remove bone spurs behind his right knee.

“Next question,” he answered when asked.

But the question was asked moments later, in a different way.

“I just told you. That [stuff] is getting old, now. That [stuff] getting real old. You’re going to have to sit in your offices and come up with some new questions. Drink a little more beer now or whatever gets you going to come up with your questions.”

Told that he’s likely going to hear that same question all season long, Garnett replied, “You’re going to get the same answer, alright?”

Eddie House drew a comparison to another famous New England athlete returning from a knee injury.

“I’m very happy he’s back, he’s moving well,” House said. “He’s even taken a few blows to the spot where he had the surgery and he bounced back up. It’s kind of like the Tom Brady effect. At first, he’s kind of ginger. He doesn’t really know until he gets hit a couple of times. ‘I can plant, I can throw.’ Like Kevin, now he can catch lobs, can plant, step-backs. He’s doing everything Kevin Garnett does.”